windows-nt/Source/XPSP1/NT/windows/richedit/re41/_dfreeze.h
2020-09-26 16:20:57 +08:00

152 lines
3.3 KiB
C++

/* @doc INTERNAL
*
* @module _DFREEZE.H Classes handle freezing the display |
*
* This module declares class used by logic to handle freezing the display
*
* History: <nl>
* 2/8/96 ricksa Created
*
* Copyright (c) 1995-1997, Microsoft Corporation. All rights reserved.
*/
#ifndef _DFREEZE_H
#define _DFREEZE_H
/*
* CAccumDisplayChanges
*
* @class This class is used to accumulate of all update to the display so
* so that at a later time the display can ask to be updated to
* reflect all the previous updates.
*/
class CAccumDisplayChanges
{
//@access Public Methods
public:
CAccumDisplayChanges(); //@cmember Constructor
~CAccumDisplayChanges(); //@cmember Destructor
void AddRef(); //@cmember Add a reference
LONG Release(); //@cmember Release a reference
void UpdateRecalcRegion( //@cmember Update the region
LONG cp, // for recalc
LONG cchDel,
LONG cchNew);
void GetUpdateRegion( //@cmember Get the update
LONG *pcpStart, // region
LONG *pcchNew,
LONG *pcchDel,
BOOL *pfUpdateCaret = NULL,
BOOL *pfScrollIntoView = NULL,
BOOL *pfRedisplayOnThaw = NULL);
void SaveUpdateCaret( //@cmember Save update
BOOL fScrollIntoView); // caret state
void SetNeedRedisplayOnThaw(BOOL fNeedRedisplay)
{
_fNeedRedisplay = fNeedRedisplay;
}
//@access Private Data
private:
LONG _cRefs; //@cmember Reference count
LONG _cpMin; //@cmember Min cp of change w.r.t.
// original text array
LONG _cpMax; //@cmember Max cp of change w.r.t.
// original text array
LONG _delta; //@cmember net # of chars changed
BOOL _fUpdateCaret:1; //@cmember Whether update
// caret required
BOOL _fScrollIntoView:1; //@cmember first parm to
BOOL _fNeedRedisplay:1; //@cmember redisplay entire control on thaw
};
/*
* CAccumDisplayChanges::CAccumDisplayChanges()
*
* @mfunc
* Initialize object for accumulating display changes
*/
inline CAccumDisplayChanges::CAccumDisplayChanges()
: _cRefs(1), _cpMin(CP_INFINITE), _fUpdateCaret(FALSE)
{
// Header does all the work
}
/*
* CAccumDisplayChanges::~CAccumDisplayChanges()
*
* @mfunc
* Free object
*
* @devnote:
* This only serves a purpose in debug mode
*
*/
inline CAccumDisplayChanges::~CAccumDisplayChanges()
{
// Nothing to clean up
}
/*
* CAccumDisplayChanges::~CAccumDisplayChanges()
*
* @mfunc
* Add another reference to this object
*/
inline void CAccumDisplayChanges::AddRef()
{
++_cRefs;
}
/*
* CAccumDisplayChanges::Release()
*
* @mfunc
* Release a reference to this object
*
* @rdesc
* 0 - no more references
* ~0 - there are still outstanding references
*
* @devnote:
* If 0 is returned the information should be retrieved from
* this object and passed on to the display so that it can
* update itself.
*
*/
inline LONG CAccumDisplayChanges::Release()
{
// When the reference count is 0, it is time to update the display.
return --_cRefs;
}
/*
* CAccumDisplayChanges::SaveUpdateCaret()
*
* @mfunc
* Save parameters for update caret
*/
inline void CAccumDisplayChanges::SaveUpdateCaret(
BOOL fScrollIntoView) //@parm First parm for UpdateCaret
{
_fUpdateCaret = TRUE;
if (!_fScrollIntoView)
_fScrollIntoView = fScrollIntoView;
}
#endif // _DFREEZE_H